Derby Monkey Tungsten Alloy Spheres measure 3.8 mm (approx 3/16") in diameter, just the right size to tweak your car to 5 ounces. This is usually accomplished by drilling 3/16 inch holes in the bottom of the car, and then gluing beads into the holes.

1 oz. - Approx 50 spheres

Tungsten is the world's 4th heaviest metal. It weighs up to 1.8x as much as lead and over 3x the weight of the Zinc/Pewter weights. This is the perfect weight for Pinewood Derby Cars.